#3 - Researcher: Dinosaur fossils come in various forms

[Administrator]

Complete Question Explanation

Strengthen. The correct answer choice is (B)

You may have had some difficulty finding the researcher’s conclusion in this stimulus, because
there is no conclusion indicator. The conclusion is that “this isn’t surprising.” Taken in context, the
conclusion is that it is not surprising that mineralized dinosaur bones and dinosaur tracks in dried
mud flats—which are two of the various forms of dinosaur fossils—are rarely found together. The
support offered for this conclusion is that dinosaur-carcass scavengers probably went to the mud flats
to find food.

The researcher’s conclusion is flawed, however. Even if the scavengers went to the mud flats to find
dinosaur carcasses to feed on, that does not necessarily mean that researchers would be unable to
find mineralized dinosaur bones there. Unless, of course, the scavengers removed the carcasses from
the flats, separating the dinosaurs’ tracks from their carcasses.

This is a Strengthen question. Our prephrase is that the correct answer choice will tell us that the
scavengers would remove the dinosaur carcasses from the mud flats, explaining why it is that
researchers do not typically find dinosaur bones and tracks there together.

Answer choice (A): The fact that dinosaur tracks are also found elsewhere does not explain why they
are not found in the flats with the dinosaur tracks.

Answer choice (B): This is the correct answer choice. Consistent with our prephrase, this answer
choice explains why researchers do not find dinosaur bones together with tracks in the mud flats.

Answer choice (C): The comparison between the number of tracks and the number of bones found is
irrelevant to the issue of why it is that tracks and bones are not found together in the mud flats.

Answer choice (D): Other types of dinosaur fossils are irrelevant to the conclusion, which had to do
with only two types of fossils, dinosaur tracks and mineralized bones.

Answer choice (E): Here, the answer choice provides another comparison, as in answer choice (C),
that is irrelevant to the conclusion. Without some other information to help us understand why the
difference in fossil preservation time matters, we cannot say that this answer choice has any effect on the conclusion.

[Cking14]

Hi,

I shouldn't have gotten this wrong, but, I just don't understand the question. The correct answer here is (B) and I put (C). I was down to these two, but ultimately picked (C) because none of the answer choices made sense to me. For some reason, I was flat out confused at what was being said.

Can someone please explain why (B) is better than (C)?

Thanks!
Chris

[Robert Carroll]

Chris,

The researcher thinks it's just to be expected that tracks and bones are not to be found together, and the researcher suggests that has something to do with the scavengers in mud flats. The researcher seems to think that you would find dinosaur tracks in mud flats, but not bones, because the scavengers have done something with the bones. Because the researcher hasn't made that connection with any evidence, the argument would be helped out by something providing the link between scavengers and the absence of dinosaur bones.

Answer choice (B) provides such a connection - dinosaur tracks are in places where dinosaurs walked, but if scavengers drag the bones away, it would make sense for the bones to be found in a different place. Thus, the two types of fossils are not found together.

Answer choice (C) doesn't explain why the two types of fossils are not found together. It simply says one type is more common. But it's perfectly consistent with that for the rarer type always to be found with the less rare type, and for the less rare type to be found alone. Thus, answer choice (C) does not explain why they would so often be separated.

Robert Carroll

[quan-tang@hotmail.com]

I dont find B attractive because Scavengers are dinosauers as well, B does not change anything since even its the case, scavengers would leave their footprint.

[Rachael Wilkenfeld]

That's the point here, quan-tang. The scavengers would leave their footprints, but NOT their bones or the bones of the animals they are scavenging. If they take the carcass away, the bones would be in a different place than the footprints, which is exactly what we see. Answer choice (B) supports the conclusion by providing factual information that is consistent with the facts we already have from the stimulus.

Hope that helps

[cd1010]

Because I had trouble finding the conclusion, I ended up reading it as having an implicit causal argument:
Cause: Creatures are scavenging mud flats
Effect: This is probably why there's no dino bones in these mud flats.

B isn't technically an alternative cause (since it's not mutually exclusive with creatures scavenging these mud flats), but it does provide more facts to say why the Effect (no dino bones) doesn't happen.

Just wanted to check that my thought process is okay regarding this, and this won't get me into trouble with other kinds of questions?

[Dana D]

Hey CD,

This is not a cause and effect argument. The researcher is stating that both dino bones and tracks aren't usually both in mud flats - the implication being that dinos weren't walking into the mud flats and then dying there. So how do the carcasses end up in the flats? The dinos must have died someplace else and then the carcass ended up in the flats.

Answer choice (B) provides support for this theory by stating that scavengers usually drag carcasses away from where they are found, and the stimulus already told us that creatures who scavenge dino carcasses go to the mud flats to find food.

Hope this helps!

[Dancingbambarina]

Surely E could be correct, as if the scavengers ate the carcass and left the bone, then since they take longer to mineralize than the tracks, the tracks could more easily be taken away by storms or whatnot while the bones remain and mineralize?

[Adam Tyson]

That's a lot of speculation, Dancingbambarina! The correct answer shouldn't need our help like that. The stimulus is saying that you'll find dried tracks in mud flats and not find bones there, and they say it makes sense since scavengers would have looked for food in mud flats. So, they go to mud flats and find dead things (because that's what scavengers eat). Why would that mean no bones near those tracks? Answer E doesn't do anything to explain that. It doesn't matter how long it takes for bones to mineralize or tracks to dry, because that still tells us nothing about why there are no bones near those tracks.

In fact, your explanation seems to suggest that we would find bones instead of tracks, which contradicts the facts in the stimulus. We know there are tracks in the mud flats, and we know that bones are rarely found near them. So, the correct answer should explain the absence of bones in mud flats, not the presence of bones and the absence of tracks. Dragging the carcasses away is a great explanation for the absence of bones. Eating the carcasses in place and leaving the bones does exactly the opposite.